The Allen-Bradley 140U-J0D3-D15 Circuit Breaker is a 3-pole, J-Frame, Inverse Time, Molded Case Circuit Breaker (MCCB) with a continuous current rating of 150 Amps. Its Horsepower ratings vary according to the voltage ratings and they can be 25 Horsepower at 200 Volts AC, 25 to 30 Horsepower at 230 to 415 Volts AC, and 50 Horsepower at 380 to 415 Volts AC. The Allen-Bradley 140U-J0D3-D15 Circuit Breaker's typical application is for the overcurrent protection of the feeder circuit of motor control devices. When used in combination with other elements such as disconnect switches and contactors, it becomes a part of a motor starter system. Inverse Time Molded Case Circuit Breakers such as the Allen-Bradley 140U-J0D3-D15 Circuit Breaker will open the circuit for overcurrent protection in a time frame that is inversely proportional to the magnitude of the overcurrents.

Larger over currents make the 140U-J0D3-D15 Circuit Breaker trip faster to disconnect the load and provide effective protection. Smaller over-currents cause a slower reaction, and the breaker will trip after a considerable amount of time has passed to allow for the process to stabilize before interrupting the circuit. Allen-Bradley designed this MCCB to provide high-speed protection against mayor over currents and to guarantee stability by waiting longer to interrupt on lower intensity events. The Interrupting Rating/Breaking Capacity of the Allen-Bradley 140U-J0D3-D15 is of 65 kA, and its magnetic trip range falls between 800 Amps and 1600 Amps. Neither the magnetic nor the thermal protection tripping points are user-configurable. Optional accessories are available to be added on the MCCB such as the Auxiliary Contacts, Rotary Operators, Internal Control Modules, and the Flex Cable Operators.